Coldest – Boomerang Nebula
1K

The coldest place outside of a laboratory is the Boomerang Nebula at 1K or minus 272.15°C, which is even colder than the Universe’s background temperature of 2.7K.

Hottest – Colliding particles in Large Hadron Collider
1000000000000000000K

When particles collide in the soon-to-open Large Hadron Collider they will reach a temperature of a billion, billion kelvin, the same temperature as the Universe mere seconds after the Big Bang.